1. Field of Invention
The present invention relates to an antenna array applying to wireless communication products, and more particularly to an antenna array capable of reducing side lobe level.
2. Description of Related Art
Along with the rapid development of wireless communication at the present, a lot of demands for products become larger. In additional to achieve standards of electrical characteristic, each of appearance and convenience of the above products is toward various aspects. In several “point-to-point” wireless communication applications, it is necessary to use an antenna array accompanying with high gain. However, the antenna array with higher gain is eager to generate side lobe level. Unfortunately, the side lobe level not only reduces gain of the antenna array, but also interferes with the system. Therefore, in the design of an antenna array, it must take more emphasizes on how to reduce the side lobe level of the antenna array.
At present, the array antenna, applying to mobile communication manufactures, is provided with several radiating members of the same shape. FIG. 7 is a top view showing a conventional antenna array unit according to prior art. The conventional antenna array unit includes a ground 11 coupled to a negative signal wire, a plurality of radiating members 12 of the same shape, and a feeding network 13 for controlling amplitude and phase of the signal through each of the radiating members 12. The feeding network 13 includes a signal feeding member 131 coupled to a positive signal wire for transmitting the signal at high frequency.
With regard to the above design of the antenna array, the plurality of radiant metal plate is used for raising the antenna directivity, further increasing gain of the antenna array. However, it is not effective to reduce the side lobe, which interferes with the transmitting signal, and then the purpose and the use is restricted. Therefore, the target of the antenna array design relies on how to reduce side lobe level. The present invention is effective to reduce the side lobe level by adding the interface current disturbing elements and is able to be used in most industry applications.